1. Field of the Invention
The present invention is generally related to fastener driving devices, and more particularly to a contact trip foot for fastener driving devices.
2. Description of Related Art
Typical pneumatic fastener driving tool actuation is achieved via the displacement of a “contact arm,” or “contact trip” through contact with a work surface, in combination with a user/operator “trigger.” The contact arm is typically constructed of stamped steel or formed wire, thereby producing an otherwise resilient member allowed to travel axially with the intended fastener driving direction, and generally adjacent to or in proximity of a “nose” of the tool through which the fastener is driven. A molded rubber covering called a “trip foot” is frequently affixed to the contact arm. The trip foot is usually removable and is intended to protect softer substrates from developing depressions as a result of direct contact with the relatively hard contact arm. The nose is typically of a geometry that forms a complete or nearly complete channel through which a fastener is guided by nature of the restrictive walls of the channel. While the channel walls provide guidance of the fastener, they also tend to obscure from view of the operator the exact location of the fastener upon exiting the nose. Further, the proximity of the contact arm to the nail exit region of the nose often contributes to this obscurity. Additionally, the trip foot may obscure the view even more.
In many applications that employ pneumatic fastener driving tools, a high degree of fastener placement accuracy is desired. Fastener placement may effect the structural integrity of a fastened joint, or significantly influence the appearance quality of cosmetically sensitive applications, such as millwork trim. Additionally, proper installation of millwork may require fasteners to be driven into irregular geometries, such as into grooves or onto raised features. It is often regarded as difficult to accurately place fasteners in these types of applications, because the contact arm and the trip foot are often shaped to engage primarily flat surfaces. Also, the cosmetically sensitive nature of most millwork materials encourages the use of the trip foot so as to reduce incidental scuffing or marking of these surfaces. The trip foot, as previously described, may reduce the operator's ability to accurately place a fastener in these applications, thereby increasing the chance of such scuffing or marking.
FIG. 1 illustrates a nail driving tool 100′ with an adapter 20′ that is attached to a contact arm 110′ for driving nails into a floorboard 40′, as disclosed by U.S. Pat. No. 6,286,742. As shown in FIG. 2, the adapter 20′ has a projection 22′ that is substantially V-shaped. This allows the tool to drive a nail into a root corner 41a′ of the floorboard 40′, as shown in FIG. 1. As shown in FIG. 2, the tip 22a′ of the protrusion 22′ falls along a nail driving axis 16′ in the nail driving direction P′. Although such a tool may be useful in flooring applications, e.g. when a nail is desired to be driven into an intersection of two substantially perpendicular surfaces, it would not be useful for driving nails into any other geometry, as the tip 22a′ of the protrusion 22′ would have the tendency to slip off of the workpiece, thereby potentially scuffing the workpiece.